Physicians have become increasingly willing to perform more aggressive interventional and therapeutic endoscopic procedures, including the removal of larger lesions (both noncancerous and cancerous). In gastrointestinal, colonic, and esophageal cancer, for example, lesions or cancerous masses may form along the mucosa and often extend into the lumens of the organs. Conventionally, the condition is treated by cutting out a portion of the affected organ wall. Physicians have adopted minimally invasive techniques called endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). EMR methods are typically used for removal of small cancerous or abnormal tissues (e.g., polyps), and ESD methods are typically used for en bloc removal of large cancerous or abnormal tissues (e.g., lesions). These procedures are generally performed with a delivery device (e.g. an endoscope). During these procedures, the mucosal layer containing the lesion is generally separated from the underlying tissue layers using a medical instrument extending through a working channel of the delivery device. As the medical instrument dissects or resects the tissue, however, the resulting tissue “flap” (e.g., already-resected portion of the mucosal layer) often obstructs the medical instrument from accessing and removing the remainder of the lesion.
As such, there exists a need for a device that provides both tissue retraction and precise cutting. In particular, there is a need for devices that can retract tissue independently of the movement of the delivery device. Such a device would allow operators to use the delivery device tip deflection to direct the cutting instruments without simultaneous moving the tissue.